Debris trap and filter cover for vent opening

ABSTRACT

A temporary debris trap and air filter which may be installed on floor vent openings in the early stages of home or commercial construction. After the floors are cut open for vent openings, the trap and filter is laid over the opening and easily affixed by adhesive strips on the flanges. The screen on top prevents construction debris from entering the duct boots and duct system and the filter below prevents dust and fine particles from entering the system while simultaneously allowing the free flow of cooled or heated air to enter the room area. The air will not be obstructed so the building and construction materials can be acclimatized during the construction period, the HVAC system can be tested and adjusted for proper air balance and the construction workers can breath filtered and conditioned air.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Provisional Application Ser. No.60/877,980 filed Jan. 2, 2007.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO A MICROFICHE APPENDIX

Not applicable.

BACKGROUND INFORMATION AND DISCUSSION OF RELATED ART

In modern home building construction, HVAC systems typically sheet metalducts that are routed to communicate with one or more vent openings inthe floor of a given room. A preformed sheet-metal “boot” is fittedinside the perimeter of each opening for connection with the duct work.Two common sized of floor vent openings are 4 in. by 10 in. and 4 in. by12 in. FIG. 1 illustrates a typical floor boot and duct installation.

It is not unusual for workers to allow the floor boot to remainuncovered during construction, and it is customary to operate the HVACsystem to control the ambient temperature in the rooms underconstruction to permit the new materials (wood, flooring, wall boards,tiles, etc.) to become acclimatized to the heated air and cooled airduring the construction period. As a result, wallboard dust, sawdust,nails, wood, metal and wire fragments, and other construction debriswill often enter the boots and accumulate inside the ducts andassociated HVAC equipment. Unless thoroughly removed when constructionis finished, the accumulated debris will impair the operation of theHVAC system by restricting the flow of conditioned air below the ratefor which the system was designed. Moreover, debris particles and dustwill be expelled from the vent openings during system operation beinhaled by the building occupants to the detriment of their health andcause undesirable odors. Government publications suggest to home ownersthat the ducts be thoroughly cleaned when “ducts are clogged withexcessive amounts of dust and debris”. EPA-402-K-97-002 October 1997.The EPA also advises that to prevent duct contamination “duringconstruction or renovation work that produces dust in your home, sealoff supply and return registers and do not operate the heating andcooling system until after cleaning up dust”.

This invention concerns particle traps and filters, particularly atrap/filter device that prevents construction debris and dust frominfiltrating the ducts of heating, ventilating and air conditioning(HVAC) systems during home building or renovation while permitting airflow.

U.S. Pat. No. 6,461,235 B2 (Oct. 8, 2002) discloses a temporary ventopening cover for covering a vent opening in a floor during buildingconstruction. A cover plate permitting air passage is secured above theopening by fasteners which are inserted through mounting holes in aperipheral flange, and into the surrounding floor surface. A filtermaterial is attached underneath the cover plate to prevent dust fromentering the duct work through the air passages in the cover plate,according to the patent.

As mentioned, the cover of the '235 B2 US patent requires the use ofnails, screws or other fasteners to secure the cover properly over avent opening. Accordingly, workers may not wish to expend the timeneeded to install such covers over a number of vent openings during thecourse of their work. Further, because nail or screw holes are formed inthe surrounding floor surface to receive the cover fasteners, additionaltime is needed to refill these holes when construction work is finishedand the covers are removed.

U.S. Pat. No. 4,712,343 (Dec. 15, 1987) embodies a re-usable shield totemporarily cover interior vent openings in residential and commercialHVAC systems. This embodiment is a vent cover only to prevent scrapconstruction debris from falling into the floor opening. It does notpermit air, heated or cooled, to come out of opening and will preventthe operation and testing of the HVAC system during the constructionperiod.

U.S. Pat. No. 6,835,129 B1 (Dec. 28, 2004) embodies an HVAC duct bootsealing device that covers the duct boot during construction and whenremoved provides an improved vent seal after construction is finished.The cover of '129B1 is a solid cover that stops debris from entering theduct system but permits no “breathing” during the construction period.

U.S. Patent #US 2004/0074214A1 (Apr. 22, 2004) is a filter devise to bemounted upon a register or air grille that will permit a slidable airfilter to be replaced from time to time. It is a housing that goes overa register, grille or diffuser and that can accept a filter of varioussizes. US '4A1 is a permanent air filter fixture that is used on floors,walls and ceilings with a raised top portion a variously shapedapertures to permit air flow. This devise is not designed for norsuitable for construction because it is a consumer product to be addedafter construction, is a permanent two-part product that has a raisedpermanent housing that allows replacement of the filter. Because it ismounted over the grille or vent opening can be a tripping hazard forconstruction workers.

U.S. Pat. No. 4,829,886 (May 16, 1989) is a thermoplastic guard devicethat is a permanent debris or liquid catcher to be placed over ventopenings. Because the air must pass around the recess and can enter orexit the vent only around the edges of the vent openings, the devicefundamentally alters the movement of air through the duct boot. Itrequires different channels for different air and heat requirements. US'886 does not filter air or acts as a filter against compound orconstruction dust but operates as a debris catcher only.

U.S. Pat. No. 6,908,115 B2 (Jun. 21, 2005) is a register opening coverto be used until the boot is installed. The devise is only used during ashort time in construction (until the boot is installed), is a completecover that permits no air flow and has no air filter ability.

BRIEF SUMMARY

The invention is a temporary debris trap and air filter for flooropenings. The device will be utilized during the construction orremodeling of residential and commercial buildings that use a forced-airsystem for heating, ventilation and air-conditioning (HVAC).

The frame of the device is made of disposable material, such ascorrugated fiberboard or re-enforced paperboard, and within the frame isa pleated, medium to high efficiency, air filter that stops smallparticles and fine construction dust from entering the boot and ductswhile permitting large volume of air to flow out the vent opening andinto the room. The top of the frame will have a screen to block largeitems and construction debris from falling into the ducts. The flangeson the device will have a peel away strip and a glue base for simpleinstallation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a section view of a typical floor opening that shows the ductboot and floor open customarily left uncovered during construction.

FIG. 2 is a top view of the invention with cut-away showing the screenand filter underneath.

FIG. 3 is a sectional view of the present invention in the flooropening.

FIG. 4 is a bottom view of the invention demonstrating the filter, theframe holding the filter and revealing the peel away, self-adhesivebottom of the flanges.

FIG. 5 shows the H frame of second embodiment.

FIG. 6 shows the top (screen side) of one of the two trap/filtersections to be inserted into the H frame of FIG. 5.

FIG. 7 shows the bottom (filter side) of one of the two trap/filtersections to be inserted into the H frame of FIG. 5.

DETAIL DESCRIPTION OF THE INVENTION

The collective views in FIGS. 2 through 4 show the invention apparatus,generally denominated 10, comprises a debris trap and filter to coverfloor vent openings to be used during construction of residential orcommercial buildings that use a forced air HVAC system. Device 10prevents common construction debris (e.g. pieces of wood, wire,wallboard scraps, nails, bottles, paper and cups) as well as compounddust, sawdust and sweeping compound from entering the duct boots throughthe floor vent openings and settling in the duct work.

FIG. 1 is a sectional view of a typical floor (1) and vent opening (2)with connecting duct boot (3) and the HVAC duct (4).

FIG. 2 shows the various components of device 10. The device 10 blocksrelatively large debris pieces including sawdust, plasterboard shavings,nails, and the like by way of a screen or mesh 5 (made of paper or wire)disposed across an upper portion of the device. Smaller debris and fineparticulates are entrapped within a filter material 8 disposed across alower portion of the device. The filter is held in the frame of device10 by cross supports 9. The filter material 8 is a high air flowmaterial such as, for example, a micron polyester sheet or a HEPA-likematerial. The filter material will be pleated in an accordion style inand across the body of device 10. The foregoing examples for the filtermaterial 8 are not intended to be limiting, and other materialspermitting a high rate of air flow with at least a medium efficiencyfilter may also be used. The screen or mesh 5 and the filter material 8are therefore sufficiently porous to allow the conditioned air to flowupward and through the device 10 to circulate freely throughout the roomunder construction.

The device 10 may be constructed with relatively inexpensive material(without limitation e.g. cardboard or reinforced paper board), and itcan be easily disposed of at the end of its temporary term of use. Thefilter material 8 may be arranged to have a pleated, accordion likeprofile, so that dust and fine particulate will be trapped in valleys ofindividual pleats, while conditioned air flows upward and out throughpeaks of the material. The device 10 may be constructed in several sizesso as to fit a given standard floor vent opening having a width of, e.g.2, 4, 6 or 8 inches, and a length of 8, 10, 12 or 14 inches.

In FIG. 3 the device 10 is shown sitting on the floor opening above theduct boot 3. The mesh screen on top 5 blocks the larger materials whilethe filter 8, held in place by the central and perimeter supports 9 ofthe frame of device 10, captures the fine particulates and dust 11 inthe accordion valleys while permitting the free flow of cooled (insummer) or heated (in winter) air 12 to flow into the room andconstruction area.

Device 10 is shown on FIG. 4 from the bottom. Here, the peel and sealself-adhesive strips on the underside of the flanges 13 are shown forthe easy installation of the device in the floor opening. The filter 8in its pleated form can be seen deposed across the length of device 10while held by the central and perimeter supports 9.

FIG. 5 shows a second embodiment of the invention. In FIG. 5 and FIG. 6views, inventive device is constructed and arranged to be expandable andcontractible to fit either one of two standard vent openings, e.g.,openings having a width of 4 inches, and a length of either 10 inches or12 inches. The device 14 includes a frame 15 having a generally “H”shape, wherein the long sides 16, 17 of the frame 15 are approximately 9inches in length. The device 14 also utilized two trap/filter sections,each having an upper mesh FIG. 6 and a lower filter material FIG. 7similar to the device 10 of FIG. 2 and each approximately 5 inches inlength. The two trap/filter sections are retained for sliding movementbetween the long sides 16, 17 of the frame 15.

A central spring loaded mechanism, e.g., leaf springs 18 are fixed tocorresponding inner short sides 19, 20 of the H frame. The springs 18are operative to urge the two sections FIG. 6 apart a sufficientdistance so that the device 50 will cover either one or two standardfloor vent openings, for example, 4 by 10 inches or 4 by 12 inches.Specifically, the device 14 may be used by (1) manually retracting thetwo sections of FIG. 6 toward one another within the frame 15 againstthe action of the springs 18 associated with the sections, (2) insertingthe device 14 inside the perimeter of the vent opening with the wiremeshes of the two sections FIG. 6 facing up, and (3) releasing thesections so that their outer short sides 21, 68 are urged by the springs18 against the facing short sides of the vent opening.

The device 14 is also retained in the vent opening by friction betweenthe outer short side 21 of the trap/filter sections FIG. 6, 7 and thesides of the vent opening against which the sections are urged by thesprings 18. Either device 10, 14 may therefore be installed convenientlyand with relative ease, and without having to create holes in the floorsurface which later must be refilled.

Flanges 6 are provided preferably on all four sides of either of thedevices 10, 14 and a self-adhesive glue is provided on each of theflanges with peel off cover strips 13. Accordingly, either device 10 or14 can be secured to the floor surface surrounding the vent openingsimply by peeling off the adhesive cover strips 13 and pressing theflanges 6 on the device against the surrounding floor surface. Theflanges may be hinged on either device 10, 14 so that they can be foldedto a storage position atop the screen 6.

1. The purpose of this invention is (1) to prevent both constructiondebris and fine compound dust and saw dust from falling into the bootand the floor duct system and infiltration the air ducts duringconstruction and before the permanent grille is put in place; (2) topermit the easy flow of hot air (in winter) or cool air (in summer) intothe construction area so that ambient room temperature is maintainedduring construction to acclimate the wall boards, wood trim, flooringmaterials and wall coverings during any season in the constructionprocess and (3) the device will be inexpensive to make, very easy toinstall, sturdy enough to last six to twelve months during theconstruction phase and easily disposable in an environmentally friendlyway.